Treatment varies depending on what caused the injury.
Jellyfish, hydroids, man of war, and anemones have tentacles that stick to the skin. These should be removed. If possible, alcohol or vinegar should first be poured over the tentacles to inactivate the stinging cells, or nematocysts. Once inactivated, the tentacles should be gently lifted from the skin. The sting site should then be washed with soap and water. Afterward, a hydrocortisone cream may be applied to the skin.
The venom of scorpion fish, lionfish, stonefish, catfish, stingrays, and sea urchins produce severe pain at the bite site. Because the venom is a protein that is broken down quickly by heat, the wound area should be immersed in water as hot as can be tolerated. The area should be left in the hot water for 60 to 90 minutes. Pieces of spines or fins are often left broken inside the skin during the sting. The person should remove these with a gloved hand. If they are unable to remove them, they should have a healthcare professional remove them with an instrument. The wound should be cleansed well with soap and water, and an antibiotic ointment applied.
Sharks, moray eels, and barracudas can injure the skin with their teeth. These animals do not have venom or poison. The wound should be cleansed with soap and water, and may need sutures, or stitches.
A person should seek medical care after a marine bite or sting. The wound needs to be examined to be sure that it is free of debris. A person may be given:
Pain can usually be controlled with acetaminophen or ibuprofen. Sometimes stronger pain medication is required.
A tetanus shot may cause tenderness at the injection site.
Antibiotics may cause:
Pain relievers may cause stomach upset.
The injured person may feel pain for many hours after the sting or bite.
The wound should be watched closely for signs of infection. Signs of infection include redness, swelling, drainage at the site, and a fever. These signs should be reported to a healthcare provider.
Usually there are no long-term effects after a marine bite or sting. Occasionally a marine bite can cause death, especially with a Portuguese man of war bite.